System is set up for use with two dogs at once-- each collar is assigned its own frequency.

No dog odor on equipment or case.

Requires two 9v batteries for the receiver and one lithium 3v CR123A battery per collar, not included.

Comes with two spare collars (spares do not come with their own transmitters).

Comes with carry case for receiver.  Carry case has a belt loop.  A small orange bag is also included, it originally held the CR123A batteries.

Comes with media originally included with the system: instruction manual, a dvd with an instructional video and explanation of product features, warranty card, and old advertisements.  Note that the warranty card won't do you much good since the company has been out of business for years.